Siberian Federal University

Postsynthetic treatment of a ZSM‑5 type zeolite with aqueous solutions of NaOH of various concentrations is carried out. Structural, acidic, and catalytic properties of the initial zeolite and treated samples are investigated in the course of conversion of straight-run gasoline fraction of oil. The main operational characteristics of the obtained high-octane gasolines are determined. The dynamics of deactivation of the initial ZSM‑5 zeolite and the sample subjected to alkaline treatment is reported and the structure of coke deposits is studied. It is found out that alkaline treatment of zeolites leads to a decrease in their crystallinity, specific surface area and specific mesopore volume, while the average pore diameter increases. Also a decrease in the concentration of acid sites with an increase in their strength is observed. As a result of changes in the properties of zeolites, the performance and stability of the catalysts obtained on their basis increase, which contributes to the improvement of the quality of gasoline formed over these catalysts during the conversion of straight-run gasoline fraction of oil